Device and method for processing plurality of resource requests in wireless communication system

ABSTRACT

Disclosed are: a communication method for merging an IoT technique with a 5G communication system for supporting a data transmission rate higher than that of a 4G system; and a system therefor. The present disclosure can be applied to intelligent services (for example, services related to smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail business, security, safety, and the like) on the basis of a 5G communication technique and IoT-related techniques. The present invention relates to a method for processing a resource allocation request of a terminal in a communication system, the method comprising the steps of: triggering a resource allocation request; confirming whether a resource for transmitting the resource allocation request has been allocated to a first subframe of at least two serving cells at the same time; and transmitting the resource allocation request to one serving cell of the at least two serving cells according to a predetermined condition when the resource is allocated to the first subframe of the at least two serving cells at the same time.

TECHNICAL FIELD

The present invention relates to a wireless communication system and,more particularly, to a method for a terminal to transmit a resourcerequest in a long term evolution (LTE) system when a base stationconfigures the terminal to transmit the resource request in a pluralityof carriers.

BACKGROUND ART

In order to satisfy increasing demands of radio data traffic after thecommercialization of a 4G communication system, efforts at developing anadvanced 5G communication system or a pre-5G communication system havebeen made. For this reason, the 5G communication system or the pre-5Gcommunication system is also referred to as a beyond-4G networkcommunication system or a post-LTE system. In order to accomplish ahigher data transfer rate, the 5G communication system considersimplementation at a super-high frequency (mmWave) band (e.g., such as a60 GHz band). In order to obviate a path loss of a radio wave andincrease a delivery distance of a radio wave at the super-high frequencyband, various techniques such as a beamforming, a massive MIMO, a fulldimensional MIMO (FD-MIMO), an array antenna, an analog beam-forming,and a large scale antenna are discussed in the 5G communication system.Additionally, for an improvement in network of the 5G communicationsystem, technical developments are made in an advanced small cell, acloud radio access network (cloud RAN), an ultra-dense network, a deviceto device (D2D) communication, a wireless backhaul, a moving network, acooperative communication, coordinated multi-points (CoMP), a receptioninterference cancellation, and the like. Besides, in the 5Gcommunication system, a hybrid FSK and QAM modulation (FQAM) and asliding window superposition coding (SWSC) are developed as advancedcoding modulation (ACM) schemes, and a filter bank multi carrier (FBMC),a non orthogonal multiple access (NOMA), and a sparse code multipleaccess (SCMA) are also developed as advanced access techniques.

Meanwhile, the Internet is evolving from a human-centric network, inwhich humans generate and consume information, into an Internet ofthings (IoT) network in which distributed things exchange and processinformation. Further, the IoT technology combines with big dataprocessing technology through connection with a cloud server or thelike, thus developing into Internet of everything (IoE) technology. Inorder to realize the IoT, relevant technologies such as sensingtechnology, wired/wireless communication, network infrastructure,service interface technology, and security technology are required.Thus, recently, technologies such as a sensor network,machine-to-machine (M2M), and machine type communication (MTC) arestudied. In the IoT environment, an intelligent Internet technology (IT)service can be provided that collects and analyzes data generated fromconnected things and thereby creates new value in a human life. The IoTcan be applied to fields of smart home, smart building, smart city,smart car or connected car, smart grid, health care, smart homeappliance, and advanced medical service through the fusion of existinginformation technology (IT) and various industries.

Accordingly, various attempts are now made to apply the 5G communicationsystem to the IoT network. For example, technologies such as a sensornetwork, machine-to-machine (M2M), and machine type communication (MTC)are implemented by techniques such as beamforming, MIMO, and arrayantennas which belong to the 5G communication technology. To apply acloud radio access network (cloud RAN) for the above-mentioned big dataprocessing technology is an example of the fusion of the 5G technologyand the IoT technology.

Meanwhile, wireless communication technologies have developed rapidly,and communication system technologies have evolved accordingly. Amongthem, the LTE system is now popularized as the fourth generation mobilecommunication technology. In LTE system, various techniques have beenintroduced to meet increasing traffic demands, and one of suchtechniques is carrier aggregation (hereinafter, referred to as CA).Compared to a typical technique that uses only one carrier forcommunication between a terminal (also referred to as user equipment(UE)) and a base station (also referred to as E-UTRAN NodeB (eNB)), theCA technique uses one main carrier and one or more subcarriers. The LTEsystem can dramatically increase the amount of transmission by thenumber of subcarriers added using the CA technique. Meanwhile, in theLTE system, the main carrier is referred to as a primary cell (PCell),and the subcarrier is referred to as a secondary cell (SCell). Whileonly one PCell exists, SCells can exist up to four in the LTE Release10. In Release 13, the standardization aims to extend up to thirty one.

On the one hand, when up to five carriers including the PCell are usedas in Release 10, a control channel (physical uplink control channel,hereinafter referred to as PUCCH) transmitted from the terminal to thebase station is transmitted only in the PCell. Information transmittedthrough the PUCCH includes information indicating whether downlink datatransmitted by the base station is successfully received (i.e., hybridautomatic repeat request (HARQ) ACK/NAK information about whetherdownlink data is received, hereinafter referred to as HARQ feedback),information indicating downlink signal state information (channel stateinformation, hereinafter referred to as CSI), information for a resourcerequest of the terminal having data to transmit through uplink (ascheduling request, hereinafter referred to as a scheduling request, aresource allocation request, or an SR), and the like.

On the other hand, when the carriers are extended up to thirty twocarriers as in Release 13, it is necessary to distribute the PUCCHbecause the amount of information is too much to transmit the PUCCH onlythrough the PCell. Thus, on the SCell as well, the transmission of thePUCCH may be permitted. Accordingly, resources for the PUCCHtransmission may be often allocated simultaneously to a plurality ofcarriers, and a method for processing this case is needed.

Additionally, in order to reduce power consumption, the terminal can usea discontinuous reception (hereinafter referred to as DRX) functioninstead of continuously receiving a signal from the base station. In theDRX defined in Release 8 of LTE, the terminal may perform a DRXoperation with a cycle of 10 ms to 2560 ms. Also, in Release 13, inorder to further reduce power consumption, it is considered to increasethe DRX cycle up to 10.24 seconds. However, typical signalingtransmitted to the terminal for setting the DRX function cannot omit(i.e., mandatory present) cycle information of 10 ms to 2560 ms.Accordingly, when the cycle up to 10.24 seconds is used, a method forindicating both new cycle information and typical cycle information isneeded.

DISCLOSURE OF INVENTION Technical Problem

The present invention has been made to solve the above problems, and itis an object of the present invention to provide an apparatus and methodfor selecting a carrier for SR transmission when resources for SRtransmission are allocated to subframes having the same time point in aplurality of carriers in a wireless mobile communication system.

Solution to Problem

According to the present invention for solving the above problems, amethod for processing a resource allocation request at a terminal in acommunication system comprises steps of triggering a resource allocationrequest, identifying whether resources to transmit the resourceallocation request are allocated to first subframes having a same timepoint in at least two serving cells, and transmitting the resourceallocation request in one of the at least two serving cells according toa predetermined condition when the resources are allocated to the firstsubframes having the same time point in the at least two serving cells.

In addition, according to the present invention for solving the aboveproblems, a method for transmitting configuration information of aterminal at a base station in a communication system comprises steps ofidentifying whether a cycle value to be set for a discontinuousreception operation of the terminal exceeds a first predetermined cyclevalue, setting first cycle information to a second predetermined cyclevalue when the first predetermined cycle value is exceeded, settingsecond cycle information to the cycle value to be set, and transmittingthe configuration information including the first cycle information andthe second cycle information to the terminal.

In addition, according to the present invention for solving the aboveproblems, a terminal for processing a resource allocation request in acommunication system comprises a communication unit configured totransmit and receive a signal to and from other network entity, and acontroller configured to trigger a resource allocation request, toidentify whether resources to transmit the resource allocation requestare allocated to first subframes having a same time point in at leasttwo serving cells, and to control the communication unit to transmit theresource allocation request in one of the at least two serving cellsaccording to a predetermined condition when the resources are allocatedto the first subframes having the same time point in the at least twoserving cells.

In addition, according to the present invention for solving the aboveproblems, a base station for transmitting configuration information of aterminal in a communication system comprises a communication unitconfigured to transmit and receive a signal to and from other networkentity, and a controller configured to identify whether a cycle value tobe set for a discontinuous reception operation of the terminal exceeds afirst predetermined cycle value, to set first cycle information to asecond predetermined cycle value when the first predetermined cyclevalue is exceeded, to set second cycle information to the cycle value tobe set, and to control the communication unit to transmit theconfiguration information including the first cycle information and thesecond cycle information to the terminal.

Specifically, when resource for SR transmission (hereinafter, SRtransmission resources) are allocated to subframes having the same timepoint in at least two cells, the terminal determines in the zero-th rulewhether there is a conflict with a measurement gap (MP). If all the SRtransmission resources allocated to two cells conflict with the MG, theterminal defers the SR transmission. If all the SR transmissionresources of two cells do not conflict with the MG the terminal appliesthe first rule. If the SR transmission resource of only one of two cellsconflicts with the MG, the terminal transmits the SR by using the SRtransmission resource of a serving cell that does not conflict with theMG.

In the first rule, the terminal determines whether there is a conflictwith a PUCCH. If both the SR transmission resource of the first cell andthe SR transmission resource of the second cell do not conflict with thePUCCH (HARQ feedback/CSI), the terminal applies the second rule. If theSR transmission resource of only one of two cells conflicts, theterminal transmits the SR by selecting the non-conflicting cell. If theSR transmission resource of the first cell conflicts with a resourceallocated for transmission of HARQ feedback (hereinafter, an HARQfeedback transmission resource), and if the SR transmission resource ofthe second cell conflicts with a resource allocated for transmission ofCSI (hereinafter, a CSI transmission resource), the terminal transmitsthe SR through the SR transmission resource of the first cell. This isbecause when the CSI transmission resource and the SR transmissionresource conflict with each other, the terminal drops the CSItransmission, and when the HARQ feedback transmission resource and theSR transmission resource conflict with each other, the terminaltransmits both together. If both the SR transmission resource of thefirst cell and the SR transmission resource of the second cell conflictwith the HARQ feedback transmission resource, the terminal applies thethird rule. If both the SR transmission resource of the first cell andthe SR transmission resource of the second cell conflict with the CSItransmission resource, the terminal defers the SR transmission.

In the second rule, the terminal determines whether the SR transmissionresource conflicts with a resource allocated for transmission of an SRS(hereinafter, an SRS transmission resource). If both the SR transmissionresource of the first cell and the SR transmission resource of thesecond cell do not conflict with the SRS transmission resource, theterminal applies the third rule. If the SR transmission resource of oneof the first and second cells conflicts with the SRS transmissionresource, the terminal transmits the SR in the non-conflicting cell.This is because when the SRS transmission resource conflicts with the SRtransmission resource, there is a possibility that the SRS transmissionwill be dropped. If both the SR transmission resource of the first celland the SR transmission resource of the second cell conflict with theSRS transmission resource, the terminal applies the third rule.

In the third rule, the terminal determines whether there is a conflictwith a transmission resource allocated for retransmission of a physicaluplink shared channel (PUSCH) (hereinafter, a PUSCH retransmissionresource). If the PUSCH retransmission is scheduled or not in both theSR transmission resource of the first cell and the SR transmissionresource of the second cell, the terminal applies the fourth rule. Ifthe SR transmission resource of the first cell conflicts with the PUSCHretransmission resource, and if the SR transmission resource of thesecond cell does not conflict with the PUSCH retransmission resource,the terminal transmits the SR in a serving cell that does not conflictwith the PUSCH retransmission resource (or transmit the SR in a servingcell that conflicts with the PUSCH retransmission so as to reducetransmission power).

The fourth rule is as follows. That is, the SR is transmitted in a cellhaving a small signal attenuation (pathloss), in a cell having lowrequired transmission power, in a serving cell that has most recentlytransmitted the SR, or in a predetermined serving cell (e.g., thePcell).

Advantageous Effects of Invention

When resources for SR transmission are allocated to a plurality ofcarriers in a wireless mobile communication system, it is possible toselect a carrier for SR transmission according to an available uplinktransmission resource of the terminal.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a structure of the LTE system to whichthe present invention is applied.

FIG. 2 is a diagram illustrating a radio protocol structure in the LTEsystem to which the present invention is applied.

FIG. 3 is a diagram illustrating improved carrier aggregation in aterminal.

FIG. 4 is a diagram illustrating a process in which a terminal transmitsan SR and is allocated a radio resource by a base station.

FIG. 5 is a diagram illustrating a method for transmitting an SRproposed by the present invention.

FIG. 6 is a diagram illustrating an operation of a terminal to which anSR transmission method proposed by the present invention is applied.

FIG. 7 is a diagram illustrating a method for selecting a cell fortransmitting an SR proposed by the present invention.

FIG. 8 is a diagram illustrating a discontinuous reception (DRX)operation of a terminal.

FIG. 9 is a diagram illustrating an operation of a base stationaccording to a second embodiment of the present invention.

FIG. 10 is a diagram illustrating a configuration of a terminalaccording to the present invention.

FIG. 11 is a diagram illustrating a configuration of a base stationaccording to the present invention.

MODE FOR THE INVENTION

Hereinafter, embodiments of the present invention will be described withreference to the accompanying drawings.

In the following description of embodiments, descriptions of techniquesthat are well known in the art and not directly related to the presentinvention are omitted. This is to clearly convey the subject matter ofthe present invention by omitting an unnecessary explanation.

For the same reason, some elements in the drawings are exaggerated,omitted, or schematically illustrated. Also, the size of each elementdoes not entirely reflect the actual size. In the drawings, the same orcorresponding elements are denoted by the same reference numerals.

The advantages and features of the present invention and the manner ofachieving them will become apparent with reference to embodimentsdescribed in detail below with reference to the accompanying drawings.The present invention may, however, be embodied in many different formsand should not be construed as limited to embodiments set forth herein.Rather, these embodiments are provided so that this disclosure will bethorough and complete, and will fully convey the scope of the inventionto those skilled in the art. To fully disclose the scope of theinvention to those skilled in the art, and the invention is only definedby the scope of claims.

It will be understood that each block of the flowchart illustrations,and combinations of blocks in the flowchart illustrations, may beimplemented by computer program instructions. These computer programinstructions may be provided to a processor of a general purposecomputer, special purpose computer, or other programmable dataprocessing apparatus to produce a machine, such that the instructions,which are executed via the processor of the computer or otherprogrammable data processing apparatus, generate means for implementingthe functions specified in the flowchart block or blocks. These computerprogram instructions may also be stored in a computer usable orcomputer-readable memory that may direct a computer or otherprogrammable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer usable orcomputer-readable memory produce an article of manufacture includinginstruction means that implement the function specified in the flowchartblock or blocks. The computer program instructions may also be loadedonto a computer or other programmable data processing apparatus to causea series of operational steps to be performed on the computer or otherprogrammable apparatus to produce a computer implemented process suchthat the instructions that are executed on the computer or otherprogrammable apparatus provide steps for implementing the functionsspecified in the flowchart block or blocks.

In addition, each block of the flowchart illustrations may represent amodule, segment, or portion of code, which comprises one or moreexecutable instructions for implementing the specified logicalfunction(s). It should also be noted that in some alternativeimplementations, the functions noted in the blocks may occur out of theorder. For example, two blocks shown in succession may in fact beexecuted substantially concurrently or the blocks may sometimes beexecuted in the reverse order, depending upon the functionalityinvolved.

The term “unit”, as used herein, may refer to a software or hardwarecomponent or device, such as a field programmable gate array (FPGA) orapplication specific integrated circuit (ASIC), which performs certaintasks. A unit may be configured to reside on an addressable storagemedium and configured to execute on one or more processors. Thus, amodule or unit may include, by way of example, components, such assoftware components, object-oriented software components, classcomponents and task components, processes, functions, attributes,procedures, subroutines, segments of program code, drivers, firmware,microcode, circuitry, data, databases, data structures, tables, arrays,and variables. The functionality provided for in the components andunits may be combined into fewer components and units or furtherseparated into additional components and modules. In addition, thecomponents and units may be implemented to operate one or more centralprocessing units (CPUs) in a device or a secure multimedia card.

The present invention relates to a method and apparatus for performing ascheduling request (SR) in a plurality of cells having a PUCCH in an LTEmobile communication system.

FIG. 1 is a diagram illustrating a structure of the LTE system to whichthe present invention is applied.

Referring to FIG. 1, as shown, a radio access network 100 of the LTEsystem is composed of base stations (evolved Node B, hereinafterreferred to as eNB, Node B, or base station) 105, 110, 115, and 120, amobility management entity (MME) 125, and a serving gateway (S-GW) 130.A terminal (user equipment, hereinafter referred to as UE or terminal)135 accesses an external network through the eNB 105˜120 and the S-GW130.

In FIG. 1, the eNB 105˜120 corresponds to a typical node B in auniversal mobile telecommunications system (UMTS) system. The eNB isconnected to the UE 135 through a radio channel and performs morecomplicated functions than the typical node B. In the LTE system, alluser traffics including a real-time service such as voice over IP (VoIP)are offered through a shared channel. Therefore, an apparatus thatperforms scheduling by collecting state information such as a UE bufferstate, an available transmission power state, and a channel state isrequired. The eNB 105˜120 performs this function. Normally, one eNBcontrols a plurality of cells.

In order to realize a transmission speed of, e.g., 100 Mbps, the LTEsystem uses orthogonal frequency division multiplexing (OFDM) as radioaccess technique at a bandwidth of, e.g., 20 MHz. In addition, the LTEsystem uses an adaptive modulation and coding (AMC) scheme thatdetermines a modulation scheme and a channel coding rate, depending on achannel state of the UE.

The S-GW 130 is an apparatus for providing a data bearer and creates orremoves the data bearer under the control of the MME 125.

The MME 125 is an apparatus for performing a variety of controlfunctions as well as a mobility management function for the UE and isconnected with a plurality of eNBs.

FIG. 2 is a diagram illustrating a radio protocol structure in the LTEsystem to which the present invention is applied.

Referring to FIG. 2, in each of the UE and the eNB, the radio protocolstack of the LTE system is composed of a packet data convergenceprotocol (PDCP) layer 205 or 240, a radio link control (RLC) layer 210or 235, a medium access control (MAC) layer 215 or 230, and a physicallayer (PHY) 220 or 225.

The PDCP layer 205 or 240 performs an operation such as IP headercompression/decompression.

The RLC layer 210 or 235 performs an ARQ operation or the like byreassembling a PDCP packet data unit (PDCP PDU) received from the PDCPlayer in a suitable size.

The MAC layer 215 or 230 is connected with several RLC layer apparatusesincluded in one UE and performs an operation of multiplexing the RLCPDUs received from the RLC layer into a MAC PDU and demultiplexing theRLC PDUs from the MAC PDU.

The PHY 220 or 225 performs an operation of channel-coding andmodulating upper layer data and then transmitting OFDM symbols thereofto the radio channel, or an operation of demodulating andchannel-decoding OFDM symbols received through the radio channel andthen delivering them to the upper layer. Also, the PHY uses hybrid ARQ(HARQ) for additional error correction, and a receiving entity transmitsone bit to a transmitting entity to notify whether a packet is receivedor not. This is referred to as HARQ acknowledge (ACK)/negativeacknowledge (NACK) information.

The downlink HARQ ACK/NACK information for the uplink transmission maybe transmitted through a physical hybrid-ARQ indicator channel (PHICH),and the uplink HARQ ACK/NACK information for the downlink transmissionmay be transmitted through a physical uplink control channel (PUCCH) ora PUSCH physical channel.

FIG. 3 is a diagram illustrating improved carrier aggregation in aterminal.

Referring to FIG. 3, one eNB generally transmits and receives multiplecarriers over several frequency bands. For example, when the eNB 305transmits uplink carriers for four cells, typically one UE transmits andreceives data by using one of the plurality of cells. However, the UEthat uses a carrier aggregation technique may transmit and receive databy using several carriers at the same time. The eNB 305 may allocate,depending on a situation, a plurality of carriers to the UE 330 usingthe carrier aggregation technique and thereby increase the datatransmission rate of the UE 330.

One forward carrier and one reverse carrier transmitted and received atone eNB constitute one cell, and the carrier aggregation technique maymean that one UE transmits and receives data simultaneously through aplurality of cells. Therefore, the maximum data transmission rateincreases in proportion to the number of carriers aggregated. In the LTERel-10 carrier aggregation technique, the eNB can configure the UE totransmit and receive data through up to five cells. In this case, one ofsuch cells necessarily has a PUCCH. A cell having the PUCCH is referredto as a primary cell (PCell), and the remaining cells having no PUCCHare referred to as a secondary cell (SCell). In addition to having thePUCCH, the PCell should be able to perform all traditional functions ofa serving cell, such as handover, RLF, and the like.

In the following description of the present invention, data receptionthrough a certain forward carrier or data transmission through a certainreverse carrier by the UE has the same meaning as datatransmission/reception using a control channel and a data channelprovided in a cell corresponding to a center frequency and a frequencyband that characterize the carrier. Although the following embodimentsof the present invention will be described on the assumption of the LTEsystem for convenience of explanation, the present invention may beapplied to various wireless communication systems that support thecarrier aggregation.

As described above, in the Rel-10 carrier aggregation technique, onlythe PCell could have the PUCCH. However, if the amount of information tobe delivered to the eNB through the PUCCH increases, it may beburdensome to transmit the information only on a single PUCCH. Inparticular, a method for transmitting and receiving data by using up to32 carriers is being discussed in LTE Rel-13, and having the PUCCH inthe SCell other than the PCell has advantages such as PUCCH loadingdispersion. It is therefore being proposed to introduce the PUCCH intothe SCell as well as the PCell.

For example, the PUCCH may be additionally introduced into one SCell 320in FIG. 3. In the present invention, the SCell having the PUCCH isreferred to as a PUCCH SCell. In the past, all PUCCH-related signalingwas delivered to the eNB through the PCell. However, since a pluralityof PUCCHs exist now, it is necessary to determine which PUCCH will beused for delivering PUCCH signaling of each SCell to the eNB.

Assuming that there are two PUCCHs as shown in FIG. 3, it will bedivided into a group of cells (first PUCCH cell group 335) using thePUCCH of the PCell and a group of cells (second PUCCH cell group 340)using the PUCCH of a specific Scell. In the present invention, such agroup is referred to as a PUCCH cell group. In the LTE mobilecommunication system, the UE reports HARQ feedback information, channelstatus information (CSI), and SR to the eNB through the PUCCH.

FIG. 4 is a diagram illustrating a process in which a terminal isallocated a radio resource by a base station.

Referring to FIG. 4, at step 410, a PDCP SDU (which will be hereinafterused together with data) to be transmitted to UE 400 is generated.

When the data is generated, the UE determines whether a radio resourcefor transmitting the data is allocated. If it is determined that theresource is not allocated, the UE may determine whether an availablePUCCH is allocated.

If it is determined that the PUCCH is allocated, the UE may transmit,using the PUCCH, a resource allocation request or a scheduling request(referred to as an SR, hereinafter) to eNB 405 at step 415. At thistime, the UE may start a timer. For example, the timer may include ascheduling request prohibition timer (sr-ProhibitTimer).

The eNB that successfully receives the SR schedules, at step 420, aradio resource for transmission of a buffer status report (hereinafterreferred to as BSR) to the UE.

If the radio resource for transmission of the BSR is not scheduled, andif the timer (sr-ProhibitTimer timer) expires, the UE may transmit theSR again. In addition, the UE may increase an SR_COUNTER value(hereinafter, referred to as a counter value) by 1 every SR transmissionattempt. If the counter value becomes equal to a predetermined value(dsr-TransMax value), the UE may attempt a random access to the eNB. Thedsr-TransMax value may be set for the UE by the eNB, and may have onevalue of {4, 8, 16, 32, 64}.

At step 425, the UE that receives a radio resource schedule for BSRtransmission may transmit the BSR by using the allocated radio resource.At this time, the BSR may be used to inform the eNB about the amount ofdata to be transmitted by the UE.

At step 430, the eNB that receives the BSR may allocate a radio resourcefor transmission of the PDCP SDU.

At step 435, the UE that is allocated the radio resource for datatransmission may transmit the data to the eNB.

Thereafter, at step 440, the eNB may transmit ACK/NACK information forthe data.

Using the SR radio resource periodically allocated, the UE may transmitthe SR to the eNB. As shown in Table 1, the SR radio resource may beallocated to the PUCCH at periods of at least 1 ms to at most 80 ms.

TABLE 1 SR period and subframe offset configuration information SR SRperiodicity configuration (ms) SR subframe Index ISR SRPERIODICITYoffset NOFFSET, SR 0-4 5 ISR  5-14 10 ISR-5 15-34 20 ISR-15 35-74 40ISR-35  75-154 80 ISR-75 155-156 2 ISR-155 157 1 ISR-157

The SR period is related to a delay time. If the SR period is configuredto be short, the UE may transmit its own SR to the eNB as soon aspossible. However, as the SR period is configured to be shorter, theshare of resources to be allocated for the SR in the PUCCH radioresources increases.

TABLE 2 PUCCH radio resource share according to SR period Number of UEswith the SR configured 18 36 72 144 288 SR 2.00% 4.00% 8.00% 16.00%32.00% periodicity 1.00% 2.00% 4.00% 8.00% 16.00% 0.40% 0.80% 1.60%3.20% 6.40% 0 0.20% 0.40% 0.80% 1.60% 3.20% 0 0.10% 0.20% 0.40% 0.80%1.60% 0 0.05% 0.10% 0.20% 0.40% 0.80% 0 0.03% 0.05% 0.10% 0.20% 0.40%

Table 2 shows the share of PUCCH radio resources according to the SRperiod. When the SR period is 10 ms or more, the share is low regardlessof the number of UEs. However, if the SR period is set as short as 1 to5 ms, the share increases. This means that the amount of radio resourcesusable for HARQ feedback information and CSI information in addition tothe SR is reduced. Therefore, it is desirable to allow the SR to betransmitted in the PUCCH of the SCell as well in order to reduce theshare while minimizing the delay time. Accordingly, the presentinvention assumes a case where the UE transmits the scheduling request(SR) in a plurality of cells having the PUCCH in the LTE mobilecommunication system. In this case, when resources for SR transmissionare simultaneously allocated to subframes having the same time point inat least two cells, it is a matter of which cell the UE transmits theSR.

FIG. 5 is a diagram illustrating a method for transmitting an SRproposed by the present invention.

Although this figure is illustrated on the assumption that there are twoserving cells, the number of serving cells is not limited to two.Referring to FIG. 5, it is assumed that the PUCCH is provided on twoserving cells, namely, a PCell 500 and one SCell 515. An SR period 510of SR transmission resources 505 in the PUCCH of the PCell does not needto be identical with an SR period 535 of SR transmission resources 520in the PUCCH of the SCell.

Meanwhile, the present invention assumes a situation where a location505 of the SR transmission resource in the PUCCH of the first cell and alocation 520 of the SR resource in the PUCCH of the second cell areallocated to the same time point. In this case, when data or the like isgenerated in the UE, the SR transmission may be triggered 525.

When the SR transmission is triggered, the UE determines in which cellthe SR is to be transmitted, based on the following conditions. In thiscase, the first cell and the second cell may be cells capable oftransmitting an arbitrary PUCCH, and need not correspond to the PCell500 and the SCell 515, respectively.

First of all, the UE determines whether to transmit the SR according tothe 0th (zero-th) rule. The 0th rule may refer to a criterion fordetermining whether to transmit the SR, depending on whether there is aconflict with a measurement gap (hereinafter referred to as MG). Theconflict between the MG and the SR transmission resource may mean that aTTI to which the SR transmission resource is allocated is a part of theMG (or the TTI to which the SR transmission resource is allocated isincluded in the MG). Hereinafter, in the present invention, a conflictbetween the SR transmission resource and a resource for transmitting anyother uplink signal may mean that a subframe in which the uplink signalis transmitted and a subframe to which the SR transmission resource isallocated (or configured) are identical or overlapped with each other onthe time axis. Alternatively, it means that the two subframes have thesame SFN and the same subframe number.

If all the SR transmission resources of the two cells for transmissionof the PUCCH conflict with the MG, the UE may defer the SR transmission.Alternatively, if the SR transmission resource of only one cellconflicts with the MG, the UE may transmit the SR in the SR transmissionresource of the serving cell that does not conflict with the MG. If allthe SR transmission resources of the two cells do not conflict with theMG, the UE may apply the first rule below. That is, the UE may select acell to transmit the SR according to the first rule.

According to the first rule, the UE may determine a cell to transmit theSR, depending on whether there is a conflict with a HARQ feedbacktransmission resource of the PUCCH and a CSI transmission resource ineach cell. If the SR transmission resources allocated in the first celland the second cell do not conflict with the HARQ feedback transmissionresource or the CSI transmission resource, the UE may apply the secondrule below. That is, the UE may transmit a cell to transmit the SRaccording to the second rule.

On the other hand, if the SR transmission resource of one of two cellsconflicts with the HARQ feedback transmission resource or the CSItransmission resource, the UE may transmit the SR by using the SRtransmission resource of the non-conflicting cell. Meanwhile, when allthe SR transmission resources allocated in the first cell and the secondcell conflict with the HARQ feedback transmission resource or the CSItransmission resource, the UE complies with the following condition.

If the SR transmission resource of the first cell conflicts with theHARQ feedback transmission resource and if the SR transmission resourceof the second cell conflicts with the CSI transmission resource, the UEmay transmit the SR in the SR transmission resource of the first cell.This is because if the CSI transmission resource of the PUCCH and the SRtransmission resource are allocated to the same subframe (conflict), theUE cannot simultaneously transmit the SR and the CSI, but if the HARQfeedback transmission resource and the SR transmission resource areallocated to the same subframe (conflict), the UE can transmit both theSR and the HARQ feedback.

In more detail, if the HARQ feedback transmission resource and the SRtransmission resource are simultaneously allocated to the same subframe,the UE may transmit HARQ feedback information in the SR transmissionresource. In this case, the eNB may measure the transmission energy ofthe SR transmission resource and thereby identify that there is data tobe sent by the UE. This corresponds to a case where the eNB allocatesPUCCH format 1a or 1b. Alternatively, the eNB may allocate a resourcecapable of simultaneously transmitting the HARQ feedback and the SR. Inthis case, the UE may simultaneously transmit both information in thecorresponding resource. This corresponds to a case where the eNBallocates PUCCH format 3. Accordingly, when the HARQ feedbacktransmission resource and the SR transmission resource conflict witheach other, the UE may transmit both the HARQ feedback and the SRwithout deterioration of the performance of the HARQ feedback. Thus, itmay be better to transmit the HARQ feedback and the SR in the same cellrather than transmit in different cells. Therefore, the UE may transmitthe SR information in the first cell which conflicts with the HARQfeedback.

If both the SR transmission resource of the first cell and thetransmission resource of the second cell conflict with the HARQ feedbacktransmission resource, the UE may apply the third rule below. That is,the UE may select a cell to transmit the SR according to the third rule.

On the other hand, if both the transmission resource of the first celland the transmission resource of the second cell conflict with the CSItransmission resource, the UE may abandon the CSI transmission andperform the SR transmission in one of the two cells. This is because theUE cannot transmit the SR and the CSI in subframes having the same timepoint. Therefore, considering information amount of the CSI, a channelstate, or the like, the UE may abandon the CSI transmission and performSR transmission in any one of two cells.

Further, the first rule may be further subdivided as follows.

The rule 1-1 may be determined depending on whether there is a conflictbetween the CSI transmission resource and the SR transmission resource.

If both the SR transmission resource of the first cell and the SRtransmission resource of the second cell conflict with the CSItransmission resource, the UE may abandon the CSI transmission andtransmit the SR in any one of the two cells. In this case, the UE mayabandon the transmission of CSI having a small amount of information tobe transmitted. Alternatively, the UE may abandon the CSI transmissionof a channel having a poor channel state and transmit the SR. However,this is only exemplary, and the UE may select, based on a predeterminedrule, the CSI to abandon transmission.

On the other hand, if the SR transmission resource of the first cellconflicts with the CSI transmission resource and if the SR transmissionresource of the second cell does not conflict with the CSI transmissionresource, the UE may transmit the SR in the SR transmission resource ofthe second cell.

In addition, if neither the SR transmission resource of the first cellnor the SR transmission resource of the second cell conflicts with theCSI transmission resource, the UE may select a cell to transmit the SRaccording to the rule 1-2.

The rule 1-2 may be determined depending on whether there is a conflictbetween the HARQ feedback transmission resource and the SR transmissionresource.

If both the SR transmission resource of the first cell and the SRtransmission resource of the second cell do not conflict with the HARQfeedback transmission resource, the UE may apply the second rule. Inaddition, if both the SR transmission resource of the first cell and theSR transmission resource of the second cell conflict with the HARQfeedback transmission resource, the UE may select a cell to transmit theSR according to the second rule.

On the other hand, if the SR transmission resource of the first cellconflicts with the HARQ feedback transmission resource and if the SRtransmission resource of the second cell does not conflict with the HARQfeedback transmission resource, the UE may transmit the SR in the SRtransmission resource of the first cell which conflicts with the HARQfeedback transmission resource.

As described above, the gist of the first rule is that, if the SRtransmission resources of two serving cells are allocated to subframeshaving the same time point, and if the SR transmission resourceconflicts with the HARQ feedback transmission resource or the CSItransmission resource in at least one serving cell, a serving cell toperform the SR transmission is selected according to the type of PUCCHtransmission.

Specifically, if the PUCCH is HARQ feedback, the UE performs the HARQfeedback transmission and the SR transmission in the same serving cell,whereas if the PUCCH is CSI, the UE performs the CSI transmission andthe SR transmission in different serving cells.

The second rule may be determined depending on whether there is aconflict with a sounding reference signal (SRS). The SRS is a referencesignal transmitted on uplink by the UE, and may be used by the eNB tomeasure an uplink signal quality.

If the SR transmission resource conflicts with the SRS transmissionresource in only one of the first and second cells, the SR transmissionmay be performed in the SR transmission resource of the non-conflictingcell. This is because there is a possibility that the SRS transmissionwill be dropped when the SRS transmission and the SR transmissionconflict with each other.

If both the SR transmission resource of the first cell and the SRtransmission resource of the second cell conflict or do not conflictwith the SRS transmission resource, a cell to transmit the SR may beselected according to the following third rule.

The third rule is determined depending on whether there is a conflictwith the PUSCH retransmission.

If the PUSCH retransmission is scheduled in both the first cell and thesecond cell, or if the PUSCH retransmission is not scheduled in both thefirst cell and the second cell, a cell to transmit the SR may beselected according to the fourth rule.

On the other hand, if there is a conflict with the PUSCH retransmissionin the first cell, and if there is no conflict with the PUSCHretransmission in the second cell, the UE may transmit the SR in theserving cell having no conflict with the PUSCH retransmission.

The fourth rule is as follows. The SR may be transmitted in a cellhaving a small signal attenuation (Pathloss) with the eNB, in a cellhaving low required transmission power (so as to minimize transmissionpower consumption), in a serving cell that has most recently transmitteda signal (so as to prevent the SR from being transmitted alternately inseveral serving cells), or in a predetermined serving cell. Thepredetermined serving cell may be, for example, the PCell or the PUCCHSCell.

FIG. 6 is a diagram illustrating an operation of a terminal to which anSR transmission method proposed by the present invention is applied.

Referring to FIG. 6, when new data is generated in the UE, the SRtransmission may be triggered at step 601.

If the SR transmission is triggered, the UE determines at step 603whether resources (SR transmission resources) capable of transmittingthe SR are allocated to subframes having the same time point in aplurality of serving cells (carriers).

If the SR transmission resources are not allocated to the subframeshaving the same time point in the plurality of serving cells, the UEtransmits at step 607 the SR in the serving cell to which the SRtransmission resource is allocated.

On the other hand, if the SR transmission resources are allocated to thesubframes having the same time point in the plurality of serving cells,the UE may select at step 605 a serving cell to transmit the SR. Theprocedure for selecting the serving cell to transmit the SR will bedescribed in detail in FIG. 7.

At step 607, the UE that selects the serving cell for SR transmissiontransmits the SR in the selected serving cell.

FIG. 7 is a diagram illustrating a method for selecting a cell fortransmitting an SR proposed by the present invention.

FIG. 7A is a diagram illustrating a method for UE to select a cell fortransmitting an SR according to the zero-th rule.

When resources capable of transmitting the SR are allocated to subframeshaving the same time point in a plurality of serving cells as in step605 of FIG. 6, the UE may determine at step 701 whether to transmit theSR, based on the first 0th rule.

At step 703, the UE may determine whether the SR transmission resourcesof two cells conflict with the MG, based on the 0th rule.

If all the SR transmission resources of the two cells in which the PUCCHis transmitted collide with the MG the UE may defer the SR transmissionat step 705.

Alternatively, if the SR transmission resource of only one of the twocells collides with the MG, the UE may transmit at step 709 the SR inthe SR transmission resource of the serving cell that does not conflictwith the MG.

On the other hand, if all the SR transmission resources of the two cellsdo not conflict with the MG, the UE may select a cell to transmit the SRaccording to the following first rule at step 707. FIG. 7B is a diagramillustrating a method for the UE to select a cell for transmitting theSR according to the first rule.

As described above, if all the SR transmission resources of two cells donot conflict with the MG, the UE may select a cell to transmit the SRaccording to the following first rule.

The first rule is determined depending on whether the HARQ feedbacktransmission resource and the CSI transmission resource in the PUCCHconflict with the SR transmission resources of two cells.

At step 723, the UE may determine whether the CSI transmission resourceand the SR transmission resource conflict with each other.

If it is determined that both the SR transmission resource of the firstcell and the SR transmission resource of the second cell conflict withthe CSI transmission resource, the UE may abandon the CSI transmissionand transmit the SR in any one of the two cells at step 725. In thiscase, the UE may abandon the transmission of CSI having a small amountof information to be transmitted. Alternatively, the UE may abandon theCSI transmission of a channel having a poor channel state and transmitthe SR. However, this is only exemplary, and the UE may select, based ona predetermined rule, the CSI to abandon transmission.

On the other hand, if the SR transmission resource of the first cellconflicts with the CSI transmission resource and if the SR transmissionresource of the second cell does not conflict with the CSI transmissionresource, the UE may transmit the SR in the SR transmission resource ofthe second cell at step 729.

Meanwhile, if both the SR transmission resource of the first cell andthe SR transmission resource of the second cell do not conflict with theCSI transmission resource, the UE may determine at step 727 whether theHARQ feedback transmission resource conflicts with the SR transmissionresource.

If the SR transmission resource of the first cell conflicts with theHARQ feedback transmission resource and if the SR transmission resourceof the second cell does not conflict with the HARQ feedback transmissionresource, the UE may transmit at step 733 the SR in the SR transmissionresource of the first cell which conflicts with the HARQ feedbacktransmission resource. This is because the UE can simultaneouslytransmit the HARQ feedback and the SR as described above.

On the other hand, if both the SR transmission resource of the firstcell and the SR transmission resource of the second cell conflict or donot collide with the HARQ feedback transmission resource, the UE appliesthe second rule at step 731.

FIG. 7C is a diagram illustrating a method for the UE to select a cellfor transmitting the SR according to the second rule.

The second rule is determined depending on a conflict between the SRStransmission resource and the SR transmission resource at step 743.

If one of the SR transmission resource of the first cell and the SRtransmission resource of the second cell conflicts with the SRStransmission resource, the UE may transmit at step 749 the SR in a cellto which the SR transmission resource which does not conflict with theSRS transmission resource is allocated. This is because there is apossibility that the SRS transmission will be dropped when the SRStransmission and the SR transmission conflict with each other.

On the other hand, if both the SR transmission resource of the firstcell and the SR transmission resource of the second cell conflict or donot conflict with the SRS transmission resource, the UE may determine atstep 747 a cell for transmitting the SR according to the following thirdrule.

FIG. 7D is a diagram illustrating a method for the UE to select a cellfor transmitting the SR according to the third rule.

The third rule is determined depending on whether a conflict with thePUSCH retransmission at step 763.

If the SR transmission resource of the first cell conflicts with thePUSCH retransmission resource and if the SR transmission resource of thesecond cell does not conflict with the PUSCH retransmission, the UE maytransmit at step 769 the SR in a serving cell that does not conflictwith the PUSCH retransmission. Alternatively, in order to lower thetransmission power, it is possible to also transmit the SR in a servingcell that conflicts with the PUSCH retransmission.

If the PUSCH retransmission is scheduled or not scheduled in both thefirst cell and the second cell, the UE may determine a cell fortransmitting the SR according to the fourth rule at step 767.

FIG. 7E is a diagram illustrating a method for the UE to select a cellfor transmitting the SR according to the fourth rule.

In the fourth rule, the UE selects a serving cell for transmitting theSR according to a predetermined condition and then transmits the SR atstep 783. The predetermined condition is as follows.

The SR may be transmitted in a cell having a small signal attenuation(Pathloss) with the eNB, in a cell having low required transmissionpower, in a serving cell that has most recently transmitted the SR, orin a predetermined serving cell.

Meanwhile, according to the second embodiment of the present invention,the UE may use a discontinuous reception (DRX) function in order toreduce power consumption instead of continuously receiving a signal fromthe eNB. In the DRX defined in Release 8 of LTE, the UE may perform aDRX operation with a cycle of 10 ms to 2560 ms. Also, in Release 13, inorder to further reduce power consumption, it is considered to increasethe DRX cycle up to 10.24 seconds.

However, typical signaling transmitted to the UE for setting the DRXfunction cannot omit (i.e., mandatory present) cycle information of 10ms to 2560 ms. Accordingly, when the cycle up to 10.24 seconds is used,a method for indicating both new cycle information and typical cycleinformation is needed.

FIG. 8 is a diagram illustrating a discontinuous reception (DRX)operation of a terminal.

The LTE UE may use the DRX function according to configuration of theeNB in order to minimize power consumption. The UE to which the DRX isapplied may monitor scheduling information in only a predeterminedphysical downlink control channel (PDCCH) in order to acquire thescheduling information. The DRX may operate in both an idle mode and aconnection mode, but operation methods are somewhat different. Thepresent invention relates to the connection mode.

In order to reduce the power consumption of the UE, the UE may operatein the DRX. The DRX operation has a DRX cycle 800 and may monitor thePDCCH only for an on-duration 805. In the connection mode, the DRX cycleis set to two values, namely, long DRX and short DRX. In general, a longDRX cycle is applied, and if necessary, the eNB may trigger a short DRXcycle by using a MAC control element (CE). After a certain time, the UEchanges the DRX operation from the short DRX cycle to the long DRXcycle. Initial scheduling information of specific UE is provided in apredetermined PDCCH only. Therefore, the UE may periodically monitoronly the PDCCH, thereby minimizing power consumption.

If scheduling information 810 for a new packet is received by the PDCCHfor the on-duration 805, the UE starts a DRX inactivity timer 815. TheUE may maintain an active state during the DRX inactivity timer. Thatis, the UE may continue PDCCH monitoring.

In addition, the UE may start an HARQ RTT timer 820. The HARQ RTT timer820 is applied to prevent the UE from unnecessarily monitoring the PDCCHduring an HARQ round trip time (RTT), and the UE does not need toperform the PDCCH monitoring during the timer operation time. However,while the DRX inactivity timer and the HARQ RTT timer are operatingsimultaneously, the UE continues the PDCCH monitoring, based on the DRXinactivity timer.

When the HARQ RTT timer expires, a DRX retransmission timer 825 may bestarted. While the DRX retransmission timer is operating, the UE shouldperform the PDCCH monitoring. Normally, during the DRX retransmissiontimer operation time, scheduling information 830 for HARQ retransmissionis received. Upon receiving the scheduling information, the UEimmediately stops the DRX retransmission timer and starts the HARQ RTTtimer again. The above operation continues until the packet issuccessfully received 835.

The configuration information related to the DRX operation in theconnection mode is sent to the UE via the RRCConnectionReconfigurationmessage. The RRCConnection Reconfiguration message is as follows.

DRX-Config ::= CHOICE { release NULL, setup SEQUENCE { onDurationTimerENUMERATED { psf1, psf2, psf3, psf4, psf5, psf6, psf8, psf10, psf20,psf30, psf40, psf50, psf60, psf80, psf100, psf200}, drx-InactivityTimerENUMERATED { psf1, psf2, psf3, psf4, psf5, psf6, psf8, psf10, psf20,psf30, psf40, psf50, psf60, psf80, psf100, psf200, psf300, psf500,psf750, psf1280, psf1920, psf2560, psf0-v1020, spare9, spare8, spare7,spare6, spare5, spare4, spare3, spare2, spare1}, drx-RetransmissionTimerENUMERATED { psf1, psf2, psf4, psf6, psf8, psf16, psf24, psf33},longDRX-CycleStartOffset CHOICE { sf10 INTEGER(0..9), sf20INTEGER(0..19), sf32 INTEGER(0..31), sf40 INTEGER(0..39), sf64INTEGER(0..63), sf80 INTEGER(0..79), sf128 INTEGER(0..127), sf160INTEGER(0..159), sf256 INTEGER(0..255), sf320 INTEGER(0..319), sf512INTEGER(0..511), sf640 INTEGER(0..639), sf1024 INTEGER(0..1023), sf1280INTEGER(0..1279), sf2048 INTEGER(0..2047), sf2560 INTEGER(0..2559) },shortDRX SEQUENCE { shortDRX-Cycle ENUMERATED { sf2, sf5, sf8, sf10,sf16, sf20, sf32, sf40, sf64, sf80, sf128, sf160, sf256, sf320, sf512,sf640}, drxShortCycleTimer INTEGER (1..16) } OPTIONAL -- Need OR } }DRX-Config2 longDRX-CycleStartOffset-r13  CHOICE { sf5120-r13 INTEGER(0..5119), sf10240-r13  INTEGER(0..10239) }

Referring to the RRCConnection Reconfiguration message, values of anon-duration timer (onDurationTimer), a DRX inactivity timer(drx-InactivityTimer), a DRX retransmission timer(drx-RetransmissionTimer), a short DRX cycle (shortDRX-Cycle), and ashort DRX cycle timer (drxShortCycleTimer) may be defined as the numberof PDCCH subframes. If subframes corresponding to the defined number ofPDCCH subframes pass after the timer starts, the timer may expire.

In the FDD, all downlink subframes belong to the PDCCH subframe, and inthe TDD, a downlink subframe and a special subframe correspond to this.

In the TDD, a downlink subframe, an uplink subframe, and a specialsubframe exist in the same frequency band. Among them, the downlinksubframe and the special subframe are regarded as the PDCCH subframe.

In order to support a DRX cycle longer than a typical DRX cycle value,the second embodiment of the present invention proposes a method for theeNB to deliver eDRX-related parameters to the UE by using firstDRX-config (which will be hereinafter used together with first cycleinformation) and second DRX-config (which will be hereinafter usedtogether with second cycle information).

In the first DRX-config, intended values may be set for theonDurationTimer, the drx-InactivityTimer, the drx-RetransmissionTimer,the shortDRX-Cycle, and the drxShortCycleTimer, and then transmitted.

However, the eNB may set a predetermined value, sf10, for a long DRXcycle start offset (longDRX-CycleStartOffset) of the first DRX-config.Since the longDRX-CycleStartOffset value should be transmittedunconditionally and since the number of required bits varies accordingto the size of the value, the eNB may set the longDRX-CycleStartOffsetvalue as sf10 and transmit it to the UE so as to use as few bits aspossible. For example, signaling of sf1024 requires 10 bits, butsignaling of sf10 requires 4 bits.

In addition, the eNB may set a desired DRX cycle value for thelongDRX-CycleStartOffset of the second DRX-config.

When the UE receives the first DRX-config and the second DRX-config atthe same time, the UE may ignore the longDRX-CycleStartOffset value ofthe first DRX-config and operate according to thelongDRX-CycleStartOffset value which is set in the second DRX-config.Therefore, using the second DRX-config, it is possible to support DRXcycles having lengths of 5.12 seconds and 10.24 seconds.

FIG. 9 is a diagram illustrating an operation of a base stationaccording to a second embodiment of the present invention.

Referring to FIG. 9, at step 910, the eNB may determine whether a cyclevalue to be set for a DRX operation of the UE exceeds a firstpredetermined cycle value.

The first predetermined cycle value may refer to the maximum value ofthe typical DRX cycle and may refer to 2560 ms.

When the cycle value to be set exceeds the first predetermined cyclevalue, typical signaling transmitted to the UE in order to set the DRXfunction cannot set a cycle exceeding the predetermined value to the UE.Therefore, the eNB should set new cycle information.

However, the eNB cannot omit cycle information included in the typicalsignaling transmitted to the UE in order to set the DRX function, sothat the eNB may set, at step 720, the first cycle information, which iscycle information included in the typical signaling, to a predeterminedcycle value.

In this case, since the first cycle information is not used by the UE,the eNB may set a cycle value of the smallest bits to the first cycleinformation. For example, the eNB may set the first period informationto 10 ms.

Then, at step 730, the eNB may set the second cycle information to thecycle value to be set.

At step 740, the eNB that sets the first cycle information and thesecond cycle information may transmit the configuration informationincluding the first cycle information and the second cycle informationto the UE in order to set the DRX function to the UE.

At this time, the UE that receives the configuration information mayignore the first cycle information and perform the DRX operationaccording to the second cycle information.

On the other hand, if it is determined at step 910 that the cycle valueto be set for the DRX operation of the UE does not exceed thepredetermined value, the eNB may set the DRX cycle through typicalsignaling.

Therefore, at step 950, the eNB may set the first cycle information tothe cycle value to be set, and transmit the configuration informationincluding the first cycle information to the UE.

FIG. 10 is a diagram illustrating a configuration of a terminalaccording to the present invention.

The terminal transmits and receives data or the like to and from anupper layer 1005, and transmits and receives control messages through acontrol message processor 1007. In case of transmission, the terminalperforms multiplexing through a multiplexer 1003 and then transmits datathrough a transmitter 1001 under the control of a controller 1009. Incase of reception, the terminal receives a physical signal through areceiver 1001, demultiplexes the received signal through a demultiplexer1003, and delivers it to the upper layer 1005 or the control messageprocessor 1007 depending on message information under the control of thecontroller 1009.

In the present invention, a transceiver 910 may transmit and receivesignals to and from other network entity. The terminal may transmit ascheduling request (SR), a buffer status report (BSR), or data throughthe transceiver 910.

The controller 1009 may control to be allocated a resource fortransmission of the BSR by transmitting the SR, and may transmit the BSRby using the allocated resource. Also, the controller 1009 may controlto be allocated a resource for transmission of data and to transmit databy using the resource.

Further, when the SR is triggered and the resource for the SRtransmission is allocated to subframes having the same time point in aplurality of serving cells, the controller 1009 may select a servingcell and transmit the SR according to the method described in FIG. 7 ofthe present invention.

Specifically, when a measurement gap (MG) does not conflict with the SRtransmission resource of one of at least two serving cells, thecontroller 1009 may transmit the SR in a cell to which the SRtransmission resource that does not conflict with the MG is allocated.

In addition, when the SR transmission resources of at least two servingcells do not conflict with the MG, the controller 1009 determineswhether the SR transmission resources of the at least two serving cellsconflict with a CSI transmission resource.

When the SR transmission resource of one of the at least two servingcells do not conflict with the CSI transmission resource, the controller1009 may transmit the SR in a cell to which the SR transmission resourcethat does not conflict with the CSI transmission resource is allocated.

In addition, when the SR transmission resources of the at least twoserving cells do not conflict with the CSI transmission resource, thecontroller 1009 determines whether the SR transmission resources of theat least two serving cells conflict with an HARQ feedback informationtransmission resource.

When the SR transmission resource of one of the at least two servingcells conflicts with the HARQ feedback information transmissionresource, the controller 1009 may transmit the SR in a cell to which theSR transmission resource that conflicts with the HARQ feedbackinformation transmission resource is allocated.

In addition, when the SR transmission resources of the at least twoserving cells conflict or do not conflict with the HARQ feedbacktransmission resource, the controller 1009 determines whether the SRtransmission resources of the at least two serving cells conflict withan SRS transmission resource.

When the SR transmission resource of one of the at least two servingcells does not conflict with the SRS transmission resource, thecontroller 1009 may transmit the SR in a cell to which the SRtransmission resource that conflicts with the SRS transmission resourceis allocated.

In addition, when the SR transmission resources of the at least twoserving cells do not conflict with the SRS transmission resource, thecontroller 1009 determines whether the SR transmission resources of theat least two serving cells conflict with a PUSCH retransmissionresource.

When the SR transmission resource of one of the at least two servingcells does not conflict with the PUSCH retransmission resource, thecontroller 1009 may transmit the SR in a cell to which the SRtransmission resource that conflicts with the PUSCH retransmissionresource is allocated.

In addition, when the SR transmission resources of the at least twoserving cells do not conflict with the PUSCH retransmission resource,the controller 1009 may transmit the SR in a cell having the smallestsignal attenuation. In the proposed method, when the SR transmission ispossible in a plurality of serving cells, the SR may be selectedaccording to an available uplink transmission resource of the UE.

FIG. 11 is a diagram illustrating a configuration of a base stationaccording to the present invention.

Referring to FIG. 11, the base station of the present invention mayinclude a communication unit 1110, a controller 1120, and a storage1130.

The communication unit 1110 may perform communication with other networkentity. The communication unit 1110 may transmit configurationinformation to a terminal.

The controller 1120 may set a cycle for a discontinuous reception (DRX)operation of the terminal. At this time, if a cycle value to be setexceeds a first predetermined cycle value, the controller 1120 may setfirst cycle information to a second predetermined cycle value and setsecond cycle information to the cycle value to be set. This is tominimize a signaling load by setting the smallest-bit cycle value to thefirst cycle information because the base station cannot omit cycleinformation included in typical signaling for setting a DRX function toterminal. This is also to set cycle information exceeding 2560 ms bynewly setting the second cycle information.

In addition, the controller 1120 may transmit configuration informationincluding the first cycle information and the second cycle informationto the terminal.

The storage 1130 may store values for configurable DRX cycleinformation. In addition, the storage 1130 may store other parametervalues for setting the DRX function. Also, the storage 1130 may storeconfiguration information including the DRX cycle information andparameter values.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it is clearlyunderstood that the same is by way of illustration and example only andis not to be taken in conjunction with the present invention. It will beunderstood by those skilled in the art that various changes in form anddetails may be made therein without departing from the subject matterand scope of the present invention.

1. A method for processing a resource allocation request at a terminalin a communication system, the method comprising steps of: triggering aresource allocation request; identifying whether resources to transmitthe resource allocation request are allocated to first subframes havinga same time point in at least two serving cells; and transmitting theresource allocation request in one of the at least two serving cellsaccording to a predetermined condition when the resources are allocatedto the first subframes having the same time point in the at least twoserving cells.
 2. The method of claim 1, wherein the transmitting stepincludes a step of: when the first subframe of a first serving cellwhich is one of the at least two serving cells is not included in ameasurement gap, transmitting the resource allocation request in thefirst serving cell.
 3. The method of claim 2, wherein the transmittingstep further includes steps of: when the first subframe of each of theat least two serving cells is not included in the measurement gap ofeach of the at least two serving cells, identifying whether the firstsubframe of a second serving cell which is one of the at least twoserving cells has the same time point as a second subframe to transmitchannel state information of the second serving cell; and when the firstsubframe of the second serving cell does not have the same time point asthe second subframe, transmitting the resource allocation request in thesecond serving cell.
 4. The method of claim 3, wherein the transmittingstep further includes steps of: when the first subframe of the at leasttwo serving cells does not have the same time point as the secondsubframe of the at least two serving cell, identifying whether the firstsubframe of a third serving cell which is one of the at least twoserving cells has the same time point as a third subframe to transmitfeedback information of the third serving cell; and when the firstsubframe of the third serving cell does not have the same time point asthe third subframe, transmitting the resource allocation request in thethird serving cell.
 5. The method of claim 4, wherein the transmittingstep further includes steps of: when the first subframe of the at leasttwo serving cells does not have the same time point as the thirdsubframe of the at least two serving cell, identifying whether the firstsubframe of a fourth serving cell which is one of the at least twoserving cells has the same time point as a fourth subframe to transmit areference signal information of the fourth serving cell; when the firstsubframe of the fourth serving cell does not have the same time point asthe fourth subframe, transmitting the resource allocation request in thefourth serving cell; when the first subframe of the at least two servingcells does not have the same time point as the fourth subframe of the atleast two serving cell, identifying whether data retransmission isscheduled through an uplink shared channel of a fifth serving cell whichis one of the at least two serving cells at the same time point as thefirst subframe of the fifth serving cell; when the data retransmissionis not scheduled through the uplink shared channel of the fifth servingcell at the same time point as the first subframe of the fifth servingcell, transmitting the resource allocation request in the fifth servingcell; and when the data retransmission is not scheduled through theuplink shared channel of all of the at least two serving cells at thesame time point as the first subframe of the at least two serving cells,transmitting the resource allocation request by using the first subframeof a cell having the smallest signal attenuation.
 6. A method fortransmitting configuration information of a terminal at a base stationin a communication system, the method comprising steps of: identifyingwhether a cycle value to be set for a discontinuous reception operationof the terminal exceeds a first predetermined cycle value; setting firstcycle information to a second predetermined cycle value when the firstpredetermined cycle value is exceeded; setting second cycle informationto the cycle value to be set; and transmitting the configurationinformation including the first cycle information and the second cycleinformation to the terminal.
 7. The method of claim 6, wherein the firstpredetermined cycle value includes 2560 ms, and the second predeterminedcycle value includes 10 ms, and wherein when the second cycleinformation is transmitted to the terminal, only the second cycleinformation is used as a cycle of the discontinuous reception operation.8. A terminal for processing a resource allocation request in acommunication system, the terminal comprising: a communication unitconfigured to transmit and receive a signal to and from other networkentity; and a controller configured to trigger a resource allocationrequest, to identify whether resources to transmit the resourceallocation request are allocated to first subframes having a same timepoint in at least two serving cells, and to control the communicationunit to transmit the resource allocation request in one of the at leasttwo serving cells according to a predetermined condition when theresources are allocated to the first subframes having the same timepoint in the at least two serving cells.
 9. The terminal of claim 8,wherein the controller is further configured to: when the first subframeof a first serving cell which is one of the at least two serving cellsis not included in a measurement gap, transmit the resource allocationrequest in the first serving cell.
 10. The terminal of claim 9, whereinthe controller is further configured to: when the first subframe of eachof the at least two serving cells is not included in the measurement gapof each of the at least two serving cells, identify whether the firstsubframe of a second serving cell which is one of the at least twoserving cells has the same time point as a second subframe to transmitchannel state information of the second serving cell; and when the firstsubframe of the second serving cell does not have the same time point asthe second subframe, transmit the resource allocation request in thesecond serving cell.
 11. The terminal of claim 10, wherein thecontroller is further configured to: when the first subframe of the atleast two serving cells does not have the same time point as the secondsubframe of the at least two serving cell, identify whether the firstsubframe of a third serving cell which is one of the at least twoserving cells has the same time point as a third subframe to transmitfeedback information of the third serving cell; and when the firstsubframe of the third serving cell does not have the same time point asthe third subframe, transmit the resource allocation request in thethird serving cell.
 12. The terminal of claim 11, wherein the controlleris further configured to: when the first subframe of the at least twoserving cells does not have the same time point as the third subframe ofthe at least two serving cell, identify whether the first subframe of afourth serving cell which is one of the at least two serving cells hasthe same time point as a fourth subframe to transmit a reference signalinformation of the fourth serving cell; and when the first subframe ofthe fourth serving cell does not have the same time point as the fourthsubframe, transmit the resource allocation request in the fourth servingcell.
 13. The terminal of claim 12, wherein the controller is furtherconfigured to: when the first subframe of the at least two serving cellsdoes not have the same time point as the fourth subframe of the at leasttwo serving cell, identify whether data retransmission is scheduledthrough an uplink shared channel of a fifth serving cell which is one ofthe at least two serving cells at the same time point as the firstsubframe of the fifth serving cell; when the data retransmission is notscheduled through the uplink shared channel of the fifth serving cell atthe same time point as the first subframe of the fifth serving cell,transmit the resource allocation request in the fifth serving cell; andwhen the data retransmission is not scheduled through the uplink sharedchannel of all of the at least two serving cells at the same time pointas the first subframe of the at least two serving cells, transmit theresource allocation request by using the first subframe of a cell havingthe smallest signal attenuation.
 14. A base station for transmittingconfiguration information of a terminal in a communication system, thebase station comprising: a communication unit configured to transmit andreceive a signal to and from other network entity; and a controllerconfigured to identify whether a cycle value to be set for adiscontinuous reception operation of the terminal exceeds a firstpredetermined cycle value, to set first cycle information to a secondpredetermined cycle value when the first predetermined cycle value isexceeded, to set second cycle information to the cycle value to be set,and to control the communication unit to transmit the configurationinformation including the first cycle information and the second cycleinformation to the terminal.
 15. The base station of claim 14, whereinthe first predetermined cycle value includes 2560 ms, and the secondpredetermined cycle value includes 10 ms, and wherein when the secondcycle information is transmitted to the terminal, only the second cycleinformation is used as a cycle of the discontinuous reception operation.